<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
  <style>

    .l2{
      color: yellow;
    }
    #l1{
      color: green;
    }

body>div>div>p{
  color: pink;
}
body div div p{
  background-color: yellow;
}
#l3{
  background-color: red;
}
a:link{
  color: green;
}
    a:visited{
      color: red;}
    a:hover{
      color: yellow;
    }
    a:active{
      color: pink;}

  </style>
</head>
<body>
<ul>
  <li>刘备</li>
  <li id="l1">关羽</li>
  <li class="l2">张飞</li>
</ul>
<p id="l3">香蕉</p>
<p id="l3" class="l2">苹果</p>
<input id="l3" type="text">
<input type="password">
<div>
  <p>p1</p>
  <div><p>p2</p></div>
  <div><div><p>p3</p></div></div>

</div>
<a href="http://www.baidu.cn">达内网站</a>

</body>
</html>